Joan of Spain

Joan of Spain (24 June 1535-7 September 1573) was an Infanta of Spain, Archduchess of Austria, and Princess of Portugal. She also served as regent for her brother Philip II of Spain from 1554 to 1559.

Biography
Joan of Spain was born in the royal court of Madrid, Spain on 24 June 1535, the daughter of Emperor Charles V and Isabella of Portugal, and the sister of Philip II of Spain and Maria of Spain. In 1552, she married her cousin Joao Manuel, Prince of Portugal, and she gave birth to their son Sebastian of Portugal eighteen days after Joao Manuel's death in 1554. She never remarried and never returned to Portugal after returning to Spain, and she founded a convent in 1557. Joan died in 1573.